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feeding behaviour

...and are both protected and nourished by the wood they inhabit. They possess ctenidia and are capable of filtering food from the sea. When elongating the burrow, they digest the wood as well. In the
Tridacnidae, symbiotic zooxanthellae (minute algal cells) are contained within the mantle tissue. The relationship between clam and algae is probably mutually beneficial, the algae having access to...